The account of Jacob wrestling with the angel is found in Genesis 32:22-32 and referenced elsewhere in Hosea 12:4. The account includes the renaming of Jacob as "Israel", literally "He who struggles with God." The account is also regularly described as Jacob wrestling with God.
Jacob spent the night alone on a riverside. There, a mysterious being—considered to be an angel or God himself—wrestled with Jacob, even striking him painfully in the hollow of his thigh. Jacob asks the being his name, and while he doesn't receive an answer, he names the place where they wrestled Peniel or Penuel. The event occurs during Jacob's journey back to Canaan.
The Masoretic text reads as follows:
The same night he arose and took his two wives, his two female servants, and his eleven children, and crossed the ford of the Jabbok. He took them and sent them across the stream, and everything else that he had. And Jacob was left alone. And a man wrestled with him until the breaking of the day. When the man saw that he did not prevail against Jacob, he touched his hip socket, and Jacob's hip was put out of joint as he wrestled with him. Then he said, “Let me go, for the day has broken.” But Jacob said, “I will not let you go unless you bless me.” And he said to him, “What is your name?” And he said, “Jacob.” Then he said, “Your name shall no longer be called Jacob, but Israel, for you have striven with God and with men, and have prevailed.” Then Jacob asked him, “Please tell me your name.” But he said, “Why is it that you ask my name?” And there he blessed him. So Jacob called the name of the place Peniel, saying, “For I have seen God face to face, and yet my life has been delivered.” The sun rose upon him as he passed Penuel, limping because of his hip. Therefore to this day the people of Israel do not eat the sinew of the thigh that is on the hip socket, because he touched the socket of Jacob's hip on the sinew of the thigh.
The account contains several plays on the meaning of Hebrew names — Peniel, Israel — as well as similarity to the root of Jacob's name (which sounds like the Hebrew for "heel") and its compound. The limping of Jacob (Ya'aqob), may mirror the name of the river, Jabbok (Yabbok sounds like "crooked" river), and Nahmanides (Deut. 2:10 of Jeshurun) gives the etymology "one who walks crookedly" for the name Jacob.